Reciprocating compressor apparatus having built-in headers



F. M. M NALL Feb. 25, 1964 RECIPROCATING COMPRESSOR APPARATUS HAVING BUILT-IN HEADERS I 2 Sheets-Sheet 1 Filed Jan. 11. 1961' INVENTOR file/[A 77% 7% a? 7 BY iwvwul-I" ATTORNEY-5.

Feb. 25, 1964 F. M. M NALL 3,122,309

RECIPROCATING COMPRESSOR APPARATUS HAVING BUILT-IN HEADERS Filed Jan 11, 1961 2 Sheets-Sheet 2 .54 W .50 56 W 42 I IN VENTOR 75 :20 Z Z7 29 BY g ATTORNEY-5.

United States Patent 3,122,369 REQEROCATEIG CGMPRESSOR APPARATUS HAVING BUILT-1N FEADERS Fredlee M. McNall, Allegany, N.Y., assignor to Dresser Industries, Inc, Dallas, Ten, a corporation of Delaware Filed Ian. 11, 1961, Ser. No. 82AM? 4 (Iiaims. (Cl. 230-189) This invention relates to reciprocating compressor apparatus, and more particularly to improved apparatus of this type in which the suction and discharge headers are substantially built into the compressor cylinder assemblies.

In certain types of reciprocating compressor apparatus, it is known practice to arrange a plurality of horizontal and laterally spaced compressor cylinder assemblies on one side of the crankcase of an engine so that the pistons in these cylinder assemblies are reciprocated by being suitably connected to the crankshaft of the engine. It is also known practice to provide a h ader or manifold pipe in vertically spaced relation with respect to the bank of horizontal cylinder assemblies and extending transversely thereof and connected to the individual cylinder assemblies by vertical pipes or conduits of reduced crosssectional area as compared to that of the header or manifold pipe. The suction and discharge valves of such cylinder assemblies are operated intermittently in relation to reciprocation of the corresponding piston. Periodically the various suction valves for each cylinder open to allow gas to be drawn from the inlet header into the cylinder interior. This occurs at different times for the various cylinders. ikewise, periodically and at different times for the various cylinders, the discharge valves open to allow compressed gas to be discharged into the discharge header. The intermittent removal from the inlet header, and the intermittent introduction into the discharge header, of gas which already fills these headers and the respective lines or pipes associated therewith create disturbances or pulses in the gas. These disturbances may be considered in the nature of wave phenomenon with a wide spectrum of frequencies. These Waves or pulses produce vibrations in the members confining the gas and if these waves or pulses are not adequately controlled, the vibrations produced thereby can be very destructive of the piping or conduits associated with the compressor apparatus.

Aside from such vibrations being destructive of the structural elements, they can also seriously damage performance of the compressor by causing the compressor to do more work to compress the gas than might otherwise be necessary. For example, assume that a high pressure we 'e front is travelling through a conventional suction header. If this Wa 'e front is opposite the suction valve when this valve is opened, more than a normal amount of gas will fill t e cylinder so as to tend to supercharge the same. For other cylinders, an expansion wave front may be opposite a suction valve so that when this valve is opened, less than a normal charge of gas will enter the cylinder.

In a related and similar manner, there may be a standing wave occurring the discharge header such that relatively hi h pressure wave fronts are opposite the discharge valves for some of the cylinders while low pressure wave fronts are opposite the discharge valves for other compression cylinders. Where a high pressure wave front stands at a discharge valve when the valve is opened, the compressed gas being discharged from the cylinder will have to work against gas at a higher pressure than normal and, therefore, less than a normal amount of compressed gas will be discharged into the header. If, on the other hand, a relativey low pressure Wave front or expansion wave stands opposite a discharge valve when this valve is opened, a pressure having less than a predetermined value is tended to be developed in the discharge header.

It is apparent that if a below normal header pressure obtains opposite the suction valve for a particular cylinder and a higher than normal pressure stands at the discharge valve for the same cylinder, this cylinder is required to do more work in transporting gas from the inlet to the outlet headers. This is inehicient operation requiring the use of more fuel for the engine driving the compressor cylinders and tends to produce engine overload.

This problem has been appreciated for some time and attempts have been made to avoid the undesirable effects of pressure variation in the inlet and outlet headers. One solution contemplated making the volume of the header to which the cylinder is connected relatively large so that the amount of gas discharged by the cylinder or drawn into it, represents only a small percentage of the header volume and hence keep the disturbance small. The disadvantage of this solution is that it required a large, bulky, heavy and expensive header construction.

Another solution to the problem heretofore proposed was to employ battles to impede mechanically the travel of the wave front which produced the undesirable pressure fluctuation. The disadvantage of this solution is that rather complicated structure was required which increased the cost of the equipment. Also, its success depended upon the production of a pressure drop or throttling effect with consequent power loss.

The foregoing disadvantages of the solutions hereto fore proposed and attempted are overcome by the present invention which contemplates eliminating any passage as such between the header and the interior of the compressor cylinder. More specifically, the purposes of the present invention are achieved by enlarging the header as it traverses a compressor cylinder so as to provide lateral branches of liberal cross sectional area to serve the valves arranged at opposite ends of the cylinder.

Accordingly, the primary object of the present invention is to provide a header construction for reciprocating compressor apparatus which produces a minimum amount of dynamic disturbances in the gas confined within the header when a quantity of gas is Withdrawn from the header (in the case of a suction header) or introduced into the header (in the case of a discharge header).

Another important object is to provide such a header construction which does not obstruct or limit accessibility to the suction and discharge valves normally arranged at each of the ends of the compressor cylinder.

Other ancillary advantages of the present invention include elimination of vibratory or other motion of the header relative to the compressor cylinder assembly, and greater rigidity and compactness of the combined structure.

Still further objects and advantages of the present invention will be apparent from the following detailed description of a preferred embodiment thereof illustrated in the accompanying drawings wherein:

FIG. 1 is a vertical sectional view of reciprocating compressor apparatus constructed in accordance with the principles of the present invention, this view being taken intermediate two adjacent compressor cylinder assemblies.

FIG. 2 is an elevational view of the outer ends of a plurality of compressor cylinder assemblies and taken on line 22, FIG. 1.

FIG. 3 is a fragmentary vertical longitudinal sectional View of one of the compressor cylinder assemblies shown in FIG. 2, this view being taken generally on line 3-3, FIG. 2.

FIG. 4 is a vertical central View thereof and taken on line 4-4, FIG. 3.

The reciprocating compressor apparatus is illustrated as including a plurality of compressor cylinder assemblies designated respectively 5, 5a and 5!). Any number of such cylinder assemblies may be provided. These cylinder assemblies are arranged with their axes horizontal, parallel and laterally spaced from one another, and project outwardly from the crankcase of an engine indicated generally at 6. The engine 6 may be of any suitable construction and includes means such as a crankshaft (not shown) connected operatively to a cross-head (not shown) guided suitably for rectilinear and reciprocable movement in a cylinder support 8 which is mounted on one side of the engine 6 and suitably connected to the inner end wall of the corresponding compressor cylinder assembly. Each of the compressor cylinder assemblies 5, 5a and 5b is shown as supported vertically by a leg or pedestal 9, 9a and 912 respectively.

Inasmuch as internally and externally each of the cornpressor cylinder assemblies 5, 5a and 5b is similar, only the assembly 5 will be described as representative of all. This assembly 5 is shown as comprising a cylinder 1% in which a piston 11 connected to a piston rod 12 is reciprocably arranged. The cylinder 16 which is circular in cross-section is shown as having its outer end closed by a removable cylinder end Wall 13 secured by a plurality of circumferentially spaced bolts or machine screws 14.

Casing means are arranged externally of the cylinder and are shown as including an end wall portion 15 at each end of the cylinder but only that at the outer end of the cylinder is illustrated in FIG. 3, generally hexagonal annular wall portions 16 and 18 surrounding the inner and outer ends, respectively, of the cylinder, and intermediate side wall portions 19 and 29 on opposite lateral sides of the cylinder. The annular portions 15 and 18 and the intermediate portions 19 and 29 are walls which are spaced from the cylinder 19. This space is divided, by a horizontal partition 21 extending radially between the casing means and cylinder 1t? and running longitudinally of the cylinder along one side thereof and by a similar horizontal partition 22 arranged on the diametrically opposite side of the cylinder 10, into an upper suction chest 23 and a lower discharge chest 24. More specifically, the partition 21 is connected to the annular wall portions 16 and 18 and intermediate side wall portion 19, and the partition 22 is connected to these annular wall portions 16 and 18 and intermediate side wall portion 20. As best shown in FIGS. 3 and 4, each of the chests 23 and 24 is generally semi-circular in cross section and extends circumferentially partway around the cylinder 10 for substantially the full length thereof, the suction chest 23 being in the upper half and the discharge chest 24 being in the lower half. Preferably as shown, the cylinder 10, casing means including end wall portions 15, annular Wall portions 16 and 18 and intermediate wall portions 19 and 2t and the partitions 21 and 22, are formed integrally as a machined casting.

The interior of the cylinder 16 is operatively connected to the upper suction chest 23 by a plurality of suction valve assemblies 25 arranged at each end of the cylinder 10, three such valve assemblies being shown at each end. The lower discharge chest 24 is arranged to be placed in communication with the interior of the cylinder 10 by a plurality of discharge valve assemblies 26 arranged at opposite ends of the cylinder 10, three such valve assemblies 26 being shown at each end of the cylinder 19. The valve assemblies 25 and 26 are of wellknown construction and each is mounted in a similar manner, also well-known in the art as illustrated typically for suction valve assemblies 25 shown in FIG. 3. Briefly reviewed here, the valve assembly is held against a radially outwardly facing annular seat 28 formed on the cylinder wall surrounding a valve opening therein, by a clamping screw 29 adjustably carried by a removable cover 30 suitably secured to the annular wall portion 13 of the casing. The inner end of the clamping screw 29 bears against a yoke or bridge 31 which in turn presses the valve housing against the seat 23. By removing the cover plate 39, the valve assembly can be removed through an opening 32 provided in the annular portion 13 of the casing.

The piston 11 is of the double-acting type so that the suction valves 25 on the leading side of the piston 11 remain closed while the discharge valves 26 on the same side of the piston are open to permit the discharge of gas therethrough into the lower discharge chest 24. Concurrently, the suction valves 25 on the trailing side of the piston 11 are open to allow gas to flow from the upper suction chest 23 into the cylinder interior, while the discharge valves 26 on the same side of the piston remain charge chest 24 for such assembly. Such discharge conduits 27 of the various compressor cylinder assemblies are communicatively joined together as hereinafter ex- 7 plained to provide an outlet header indicated generally at 51in FIG. 2.

Considering the upper suction conduit 17, an upwardly arched wall 33, generally of semi-cylindrical shape in cross-section, is shown as joined integrally with the cas ing wall portions 16, 18, 19 and 26. To increase the rigidity of the upper arched wall 33 and to improve the heat exchange capabilities of the suction chest 23, this Wall 33 is shown asformed externally with a series of parallel and laterally spaced outstanding ribs or fins 34 which follow the curvature of the wall 33. The axis of the suction conduit 17 is shown as extending horizontally and perpendicularly across the axis of the cylinder 10. The ends of the arched wall 33 jointly with the integral casing side wall portions 19 and 2t? define a circular opening 40 at each end of the suction conduit 17.

With regard to the lower discharge conduit 27, a downwardly arched wall 35, generally of semi-cylindrical shape in cross-section, is shown as joined integrally with the casing wall portions 16, 18, 19 and 20. The arched wall 35 also is shown as formed externally with a series of parallel and laterally spaced outstanding ribs or fins 36 which follow the curvature of the wall 35. The axis of the discharge conduit 27 is shown as extending horizontally and perpendicularly across the axis of the cylinder 10. tegral casing side Wall portions 19 and 20 define a circular opening 41 at each end of the discharge conduit 27.

Each end of the upper arched wall 33 terminates in an outwardly extending attaching flange 38 which has an outer axially facing surface coplanar with and an extension of the outer and vertical surface of the respective casing lateral side wall portion 19 or 20. An annular boss 52 extends axially outwardly from the flange 38 and is concentric with the axis of the suction conduit 17.

Similarly, each end of the lower arched wall 35 terminates in an outwardly extending attaching flange 39 which is coplanar with and an extension of the outer and vertical surface of the respective casing lateral side wall portion 19 or 20. Hence, the vertical outer surface of the lower flange 39 is coplanar with that of the upper flange 33 on each lateral side of the cylinder 10. An annular boss 53 extends axially outwardly from the lower The ends of the arched wall 35 jointly with the ini flange 39 and is concentric with the axis of the discharge conduit 27.

Referring to FIG. 2, it will be seen that the right-hand attaching flange 38 opposes a left-hand attaching flange 38a on the compressor assembly 5a and is spaced therefrom. These two flanges 38 and 38a are shown as connected together by a tubular member 42 having outwardly extending annular attaching flanges 4-3, 43 at opposite ends. The cylindrical bore or passage 4-8 of the tubular member 42 has the same diameter as the alined end openings 4% of the suction conduit 17. An annular boss 57 extends axially outwardly from each flange 43 and is concentric with the bore 48 and is adapted to abut the end face of the opposing boss 52. Nut and bolt fastening means 44 are provided at circumferentially spaced intervals for drawing opposing flanges 3S and 43 toward each other and to seal the joint between the ends of the tubular member 42 and the associated casings of the two compressor cylinder assemblies on opposite sides thereof. The members 42 with their attaching flanges 43 resemble spools which can be interposed between the opposing and spaced pairs of attaching flanges of adjacent compressor cylinder assemblies.

Similarly, tubular members or spools 45 having at each end a radially outwardly extending annular attaching flange 46 and axially extending boss 47, are interposed between the opposing and spaced ends of the discharge conduits 27 of adjacent compressor cylinder assemblies. The cylindrical bore or passage 49 of the lower tubular member 45 has the same diameter as the alined end openings 41 of the lower discharge conduit 27. The attaching flanges 39 and 46 are drawn together by bolt and nut fastening devices 54 arranged at circumferentially spaced intervals.

Referring to FIGS. 2 and 3, it will be seen that the inlet and outlet headers 5i} and 51, respectively, are parallel to each other, are arranged on opposite sides of the various compressor cylinder assemblies, and extend perpendicularly to the axes of these assemblies. The upper suction chest 23 of each compressor cylinder assembly has lateral portions 55 and 56 which are arranged on opposite sides of the enlarged central space formed by the juncture of the suction conduit 17 and chest 23, and these lateral portions 55 and 55 lead toward opposite ends of the corresponding cylinder at which the suction valves assemblies are arranged. In this manner, liberal and unrestricted communication is provided between the suction chest adjacent the suction valve assemblies at opposite ends of the cylinder and the enlarged central portion of the upper suction conduit.

Similarly, the lower discharge chest 2 has lateral portions on opposite sides of the enlarged central space formed by the juncture of the discharge conduit 27 and chest 24, to serve the discharge valve assemblies 2:) arranged at opposite ends of the cylinder. These lateral portions also have a liberal cross-section so as to provide unimpeded communication and passage for the gas discharged by the valve assemblies 26 into the lower discharge conduit.

it will be noted that the upper and lower headers and 51 have direct communication with the respective gas chests surrounding the cylinders by reason of intercepting the same, and any vertical passages communicat ing the chests with the headers are eliminated.

It has been found that reciprocating apparatus constructed as hereinabove described eliminates the undesirable vibrations present in apparatus as heretofore constructed and otherwise accomplishes the objects stated. Modifications of the particular construction illustrated will be apparent to those skilled in the art. Accordingly, the embodiment shown and described is illustrative and not limitative of the invention which is to be measured by the scope of the appended claims.

What is claimed is:

1. In reciprocating gas compressor apparatus, the combination comprising a cylinder, a removable end wall for said cylinder, means providing a suction chest on one side of said cylinder, said suction chest having end portions severally adjacent the ends of said cylinder and also having a communicating central portion which is enlarged with respect to such end portions in a direction radially outwardly of said cylinder and which extends transversely of said cylinder, said enlarged portion of said suction chest having openings on opposite sides of said cylinder, removable suction valve means arranged on said cylinder at opposite ends thereof and arranged to establish communication between the interior of said cylinder and each of said end portions of said suction chest, means providing a discharge chest on the other side of said cylinder, said discharge chest having end portions severally adjacent the ends of said cylinder and also having a communicating central portion which is' enlarged with respect to such end portions in a direction radially outwardly of said cylinder and which extends transversely of said cylinder, said enlarged portion of said discharge chest having openings on opposite sides of said cylinder, and removable discharge valve means arranged on said cylinder at opposite ends thereof and arranged to establish communication between the interior of said cylinder and each of said end portions of said discharge chest, all of said valve means being removable other than by removing said end wall.

2. In reciprocating gas compressor apparatus, the combination comprising a cylinder, a removable end wall for said cylinder, casing means having a wall surrounding said cylinder in spaced relation thereto, partition means extending between said cylinder and easing means and dividing the space therebetween into suction and discharge chests, removable suction valve means arranged on each of said cylinders adjacent each end thereof and operative to establish communication between said suction chest and the interior of said cylinder, and removable discharge valve means arranged on each of said cylinders adjacent each end thereof and operative to establish communication between said discharge chest and the interior of said cylinder, all of said valve means being removable other than by removing said end wall, the portion of said wall for each of said chests and intermediate the valve means associated severally therewith and at opposite ends of said cylinder being centrally and gradually spaced radially outwardly a greater distance from said cylinder and formed to provide openings on opposite sides of said cylinder thereby to provide a conduit extending transversely of said cylinder and inter cepting the corresponding one of said chests.

3. In reciprocating gas compressor apparatus, the combation comprising a cylinder, means providing a suction chest on one side of said cylinder, said suction chest having end portions severally adjacent the ends of said cylinder and also having a communicating central portion which is enlarged with respect to such end portions in a direction radially outwardly of said cylinder and which extends transversely of said cylinder, said enlarged portion of said suction chest having openings on opposite sides of said cylinder, removable suction valve assemblies arranged on said cylinder at opposite ends thereof and arranged to establish communication between the in terior of said cylinder and each of said end portions of said suction chest, means providing a discharge chest on the other side of said cylinder, said discharge chest having end portions severally adjacent the ends of said cylinder and also having a communicating central portion which is enlarged with respect to such end portions in a direction radially outwardly of said cylinder and which extends transversely of said cylinder, said enlarged portion of said discharge chest having openings on opposite sides of said cylinders, removable discharge valve assemblies arranged on said cylinder at opposite ends thereof and arranged to establish communication be tween the interior of said cylinder and each of said end portions of said discharge chest, and means arranged to provide an access opening into said end portions of said chests opposite each of said valve assemblies and of a size to permit passage of the same therethrough.

4. In reciprocating gas compressor apparatus, the combation comprising a cylinder, casing means having a wall surrounding said cylinder in spaced relation thereto, partition means extending between said cylinder and casing means and dividing the space therebetween into suction and discharge chests, suction valve assemblies removably arranged on each of said cylinders adjacent each end thereof and operative to establish communication between said suction chest and the interior of said cylinder, discharge valve assemblies removably arranged on each of said cylinders adjacent each end thereof and operative to establish communication between said discharge chest and the interior of said cylinder, the portion of said Wall for each of said chests and intermediate the valve means associated severally therewith and at opposite ends of said cylinder being centrally and gradually spaced radially outwardly a greater distance from said cylinder and formed to provide openings on opposite sides of said cylinder thereby to provide a conduit extending transversely of said cylinder and intercepting the corresponding one of said chests, said wall opposite each of said valve means having an opening through which such valve means may pass, and a removable cover for each of said openings, whereby all said valve means are accessible and removable through said openings.

References Qited in the file of this patent UNITED STATES PATENTS 452,537 Winkler May 1 9, 1891 742,949 Worthington Nov. 3, 1903 746,344 Krohn Dec. 8, 1903 1,092,495 Lipman Apr. 7, 1914 1,172,581 Cheney Feb. 22, 1916 1,285,792 Raynes Nov. 26, 1918 1,299,211 Neeson Apr. 1, 1919 1,616,072 Allerton Feb. 1, 1927 1,718,296 Labus June 25, 1929 2,509,022 Turnquist May 23, 1950 2,766,701 Giraudeau Oct. 16, 1956 

1. IN RECIPROCATING GAS COMPRESSOR APPARATUS, THE COMBINATION COMPRISING A CYLINDER, A REMOVABLE END WALL FOR SAID CYLINDER, MEANS PROVIDING A SUCTION CHEST ON ONE SIDE OF SAID CYLINDER, SAID SUCTION CHEST HAVING END PORTIONS SEVERALLY ADJACENT THE ENDS OF SAID CYLINDER AND ALSO HAVING A COMMUNICATING CENTRAL PORTION WHICH IS ENLARGED WITH RESPECT TO SUCH END PORTIONS IN A DIRECTION RADIALLY OUTWARDLY OF SAID CYLINDER AND WHICH EXTENDS TRANSVERSELY OF SAID CYLINDER, SAID ENLARGED PORTION OF SAID SUCTION CHEST HAVING OPENINGS ON OPPOSITE SIDES OF SAID CYLINDER, REMOVABLE SUCTION VALVE MEANS ARRANGED ON SAID CYLINDER AT OPPOSITE ENDS THEREOF AND ARRANGED TO ESTABLISH COMMUNICATION BETWEEN THE INTERIOR OF SAID CYLINDER AND EACH OF SAID END PORTIONS OF SAID SUCTION CHEST, MEANS PROVIDING A DISCHARGE CHEST ON THE OTHER SIDE OF SAID CYLINDER, SAID DISCHARGE CHEST HAVING END PORTIONS SEVERALLY ADJACENT THE ENDS OF SAID CYLINDER AND ALSO HAVING A COMMUNICATING CENTRAL PORTION WHICH IS ENLARGED WITH RESPECT TO SUCH END PORTIONS IN A DIRECTION RADIALLY OUTWARDLY OF SAID CYLINDER AND WHICH EXTENDS TRANSVERSELY OF SAID CYLINDER, SAID ENLARGED PORTION OF SAID DISCHARGE CHEST HAVING OPENINGS ON OPPOSITE SIDES OF SAID CYLINDER, AND REMOVABLE DISCHARGE VALVE MEANS ARRANGED ON SAID CYLINDER AT OPPOSITE ENDS THEREOF AND ARRANGED TO ESTABLISH COMMUNICATION BETWEEN THE INTERIOR OF SAID CYLINDER AND EACH OF SAID END PORTIONS OF SAID DISCHARGE CHEST, ALL OF SAID VALVE MEANS BEING REMOVABLE OTHER THAN BY REMOVING SAID END WALL. 